1. Field of the Invention
This invention relates to prefabricated building panels, and more particularly, to panels having a metal load-bearing structure which can be filled with a hardenable material. The hardenable material need not have substantial load-bearing characteristics.
2. Description Of The Prior Art
The prior art relating to prefabricated building panels is directed primarily at walls filled with a cementitious mixture which, when hardened, becomes a load-bearing, structural member of the wall. U.S. Pat. No. 1,031,926 to Hansbrough has a metal outer structure formed of angle iron and utilizing reinforcing rod. The structure is filled with concrete which becomes an integral load-bearing part of the structure. In the present invention, the load-bearing structure is built prior to being filled with the hardenable material, and the invention is therefore not limited to a load-bearing material such as concrete. U.S. Pat. No. 3,760,540 to Latoria discloses a similar structure to Hansbrough but uses channel iron members having openings inwardly directed. Neither of these previous patents discloses a structure utilizing a metal member having substantially C-shaped cross section such that an interlocking effect is achieved when the structure is filled with a hardenable material, as does the present invention.
U.S. Pat. No. 1,813,909 to Brainard et al. shows a building panel having a layer of insulating material between two layers of a cementitious material. Again, in Brainard, the cementitious material is load-bearing and helps support the entire structure. This is distinguished from the present invention which, although having an insulating layer, may utilize a material of lighter weight and lesser strength than a load-bearing material such as concrete.